1. Field of the Invention
This invention relates generally to data display on small screen devices, and more particularly to systems and methods for presenting time related data on small screen devices.
2. Description of the Related Art
Recent advancements in cellular phone technologies have made instant communication easier and faster than ever. Originally analog, cellular systems have evolved to a digital format, which has enabled the cellular phone to become a smart phone having increased data storage capability and access to the Internet. Cellular phone systems generally include numerous base stations, each covering a small geographic area, known as a “cell,” that slightly overlaps adjacent cells at the borders. The cells, combined with low power transmitters, provide a communication network for cellular phone users.
The reduced costs and instant communication ability of the cellular phone has resulted in an increased dependents on cellular phones when away from the home, office, and when traveling. Moreover, because of the memory available in most cellular phones, increasingly complex data can be stored in cellular phone memory, such as electronic task list data.
Task list data is an example of a time related data set. Individuals often use time related data, such as task lists and weekly viewers, to schedule their day, week, and/or month. Such data provides the user with a means to plan their day, and also provides reminders for individual appointments. Unfortunately, small screen devices such as cellular phones have a limited amount of screen space to display information, generally in the range of about 108×96 pixels. Even when higher resolutions are utilized, the small size of the screen limits the information that can be displayed. For example, at a resolution of 1024×768 pixels, the screen can only display ten rows of lines if the screen is two inches in height. As a result, conventional small screen devices are limited in the level of detail they provide to the user. In particular, conventional small screen devices do not provide a user with a broad overview of their schedule, which is often needed to help plan a day.
FIG. 1 is a diagram showing an exemplary prior art small screen user interface (UI) for a task list 100. The exemplary prior art task list UI 100 generally includes a signal strength indicator 102 and a battery power indicator 104 in addition to the phonebook data. The signal strength indicator 102 informs the user as to the signal strength currently available at the user's current location, while the battery power indicator 104 informs the user as to the current power available in cellular phone's battery. The task list data generally includes a date title bar 106 and a plurality of task entries 108a-108c. Each task entry includes a task time 110a-110c and a corresponding task description 112a-112c. 
As illustrated in FIG. 1, the prior art task list UI 100 only provides the user with a list of discrete data, namely, a list of task entries 108a-108c. The problem with the prior art task UI 100 is that the user is not provided with an informative overview of the day's schedule. That is, the user cannot easily determine what time is free and what time is accounted for using the prior art task list UI 100. For example, the user must subtract start and end times of the discrete task entries 108a-108c to determine which times are free. Further, the prior art task list UI 100 does not provide the user with a visual representation of the task schedule, which can be easily glanced at to get an overview of the day's tasks and appointments.
Moreover, if more tasks occur during a particular day than can be displayed at once on the small screen device, the user cannot determine the schedule for events not currently listed. In order to determine the schedule for times not currently displayed, the user must scroll down the task list to reveal the concealed tasks. For example, in FIG. 1, if more than three tasks are present in the day, not all the tasks will be listed on the screen at once. In addition, the user cannot determine at a glance whether more than three tasks are present during the current day. Also, if additional tasks are present, the user must scroll down to the concealed tasks to determine when they occur and how much time is required for each task.
In view of the foregoing, there is a need for techniques for presenting time related data on small screen devices. The time related data should be presented such that an overview of schedule is provided to the user, to allow the user to better plan their schedule. Further, the time related data should be presented such that a user can easily determine when free time is available between tasks, which can be used to insert future tasks or appointments. Moreover, the presentation of the time related data should allow the user to determine the schedule for entire time represented by the schedule. In particular, the user should be presented with information regarding time requirements for tasks not currently listed on the screen, but present in the current schedule.